Alpine winds will pick up again tonight. If the spike lasts for awhile, expect new windslabs and possibly a jump to considerable in the alpine. Be prepared for a quick change.
Weather Forecast
Another chilly morning is expected. Lows will be around -15 to -20. Daytime highs will be around -7. No snow to speak of, alpine winds will pick up during the day and expect light cloud cover for most of the day.
Avalanche Summary
Nothing today.
Snowpack Summary
No major change in the region's snowpack overnight. We did receive a hint of snow, but in the grand scheme of things, 4cm is irrelevant. What is relevant though is the spike in alpine winds from a few days ago. The alpine has isolated, new windslabs on north to south aspects. The cold north wind caused some reverse loading. The slabs tend to be near ridges, and not too big. Treeline snow is generally facetted and weak with a hint of the windslabs from the last week. These slabs are less reactive as the bond gets better with the layers below. Valley bottom snow is very weak. Breaking a new trail is a lot of work!
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Deep Persistent Slabs
Deep Persistent Slab avalanches are the release of a thick cohesive layer of hard snow (a slab), when the bond breaks between the slab and an underlying persistent weak layer deep in the snowpack. The most common persistent weak layers involved in deep, persistent slabs are depth hoar or facets surrounding a deeply buried crust. Deep Persistent Slabs are typically hard to trigger, are very destructive and dangerous due to the large mass of snow involved, and can persist for months once developed. They are often triggered from areas where the snow is shallow and weak, and are particularly difficult to forecast for and manage.